Lease annual increase rate of base rent.

No definition available.

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Namespace Prefix:	pstv_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Rent abatement.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Area of land held.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Face amount or stated value per share of common stock.

+ References

+ Details

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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(16)(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Description of lessee's operating lease that has not yet commenced. Including, but not limited to, nature of involvement with construction or design of underlying asset for lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (g)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-4

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=stpr_TX
Namespace Prefix:
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Subsequent Events - Additional Information (Details)	Aug. 10, 2026 USD ($) ft²	Oct. 16, 2025 USD ($) ft²	Jun. 30, 2026 $ / shares shares	Apr. 01, 2026 $ / shares	Dec. 31, 2025 $ / shares shares	Aug. 07, 2025 $ / shares
Subsequent Event [Line Items]
Common stock, shares authorized (in shares) \| shares			2,000,000,000		2,000,000,000
Common stock, par value (in dollars per share) \| $ / shares			$ 0.001	$ 0.001	$ 0.001	$ 0.001
Area of space		11,370
Monthly base rent \| $		$ 58,745
LG 1 Property Owner LP
Subsequent Event [Line Items]
Area of space		11,370
Lessee, operating lease, description		The Houston Lease is expected to commence on or about November 1, 2026.
Monthly base rent \| $		$ 58,745
Lease annual increase rate of base rent		3.00%
Lessee, operating lease, term of contract		120 months
Subsequent Event [Member]
Subsequent Event [Line Items]
Monthly base rent \| $	$ 188,443.83
Subsequent Event [Member] \| LG 1 Property Owner LP
Subsequent Event [Line Items]
Lease annual increase rate of base rent	3.00%
Rent abatement	7 months
Lessee, operating lease, term of contract	120 months
Subsequent Event [Member] \| Building [Member] \| LG 1 Property Owner LP
Subsequent Event [Line Items]
Area of space	36,473
Subsequent Event [Member] \| Building [Member] \| LG 1 Property Owner LP \| 6420 Levit Green Boulevard, Houston, Texas 77021
Subsequent Event [Line Items]
Area of space	25,103